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Physical Macrohardness of the Kinetic Indentation of the Material: Function and Universal Unit of Measure (Part 1)
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作者 Shtyrov Nikolay 《Journal of Mechanics Engineering and Automation》 2023年第3期64-78,共15页
Three directions of development of kinetic indentation methods.Physical-energetic analysis of the indentation force diagram according to ISO 14577.Physical theory and universal criterion for the macrohardness of a mat... Three directions of development of kinetic indentation methods.Physical-energetic analysis of the indentation force diagram according to ISO 14577.Physical theory and universal criterion for the macrohardness of a material.Model of the physical process,thermomechanical potential,function of the state of the kinetic macroindentation process.Method for determining the physical function and unit of measurement of the kinetic macrohardness of a material.The ratio of the values of the empirical(standard)and physical macrohardness of the material.Physical reason for the appearance of the size effect in empirical indentation methods.The principle of determining the standard value of physical macrohardness. 展开更多
关键词 Review physical theory of kinetic indentation method for determining physical macrohardness of the material
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Physical Properties of the Function and Number of Empirical Macrohardness of the Material: Universal Physical Unit of Measurement of Macro Hardness (Part 2)
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作者 Shtyrov Nikolay 《Journal of Mechanics Engineering and Automation》 2023年第3期79-91,共13页
Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical com... Results of analytical studies of the physical properties of the function and number of empirical macrohardness based on the standard experimental force diagram of kinetic macroindentation by a sphere.An analytical comparison method and a criterion for the similarity of the physical and empirical macrohardness of a material are proposed.The physical properties of the hardness measurement process using the Calvert-Johnson method are shown.The physical reasons for the size effect when measuring macrohardness are considered.The universal physical unit and standard of macrohardness of kinetic macroindentation by a sphere is substantiated. 展开更多
关键词 physical theory of kinetic indentation method for determining the function and number of physical macrohardness ratio of empirical and physical macrohardness of a material universal physical unit of macrohardness.
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Structure and physical properties of the Earth's interior
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作者 臧绍先 周蕙兰 +1 位作者 魏荣强 周元泽 《Acta Seismologica Sinica(English Edition)》 CSCD 2003年第5期522-533,共12页
The studies on the structure and physical properties of the Earths interior done by Chinese geophysicists from 1999 to 2002 were reviewed in this paper. It includes several research areas: the structure of the Earths ... The studies on the structure and physical properties of the Earths interior done by Chinese geophysicists from 1999 to 2002 were reviewed in this paper. It includes several research areas: the structure of the Earths interiors using seismic tomography, anisotropy of the upper mantle in China and its adjacent areas, quality factor Qb for S waves, subduction zone, mantle discontinuities, physical properties of Earths materials and others. The review concerns mainly the contents, the methods and the results of the studies. It can be seen that new progress in the study on the structure and physical properties of the Earths interior has been made in the last 4 years in China. It is shown on three aspects: advancement made on some preexistent areas; pioneering on some new fields and new methods adopted. 展开更多
关键词 structure of the Earths interior physical property of the Earths materials seismic tomography ANISOTROPY subduction zone mantle discontinuity
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Experimental study on the movement law of overlying rock non-pillar coal overhead mining
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作者 LI Yong ZHENG Jing +5 位作者 WANG Feng-nian MA Xin-gen ZHANG Rui-xue SUN Ying-ying YIN Jian-bin TAO Zhi-gang 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1759-1773,共15页
Pillarless coal mining technology is a new practical technology.Based on the compensating mechanical behavior of the Negative Poisson’s Ratio(NPR)anchor cable on the roof,the roadway was successfully retained by the ... Pillarless coal mining technology is a new practical technology.Based on the compensating mechanical behavior of the Negative Poisson’s Ratio(NPR)anchor cable on the roof,the roadway was successfully retained by the top cutting and pressure relief technology.This study utilizes the Digital Speckle Monitoring(DIC monitoring),stress-strain monitoring,and infrared thermal imaging systems to conduct physical model experiment of similar materials from the displacement,stress-strain,and temperature fields to investigate in depth the fracture change law of the overlying rock.In addition,it uses FLAC3D numerical simulation to invert the surface displacement settlement.The results show that the non-pillar overhead mining under the 110 mining method has little influence on the rock crack in the middle of the coal seam,and the crack development area is mainly concentrated in the overlying rock mass of the upward coal seam.The compensatory mechanical behavior of NPR anchor cable and the dilatation characteristics of rock mass have a good effect of retaining roadway along goaf,and can also reduce surface settlement.The 110 mining method provides a scientific basis for ecological environment protection and the development of other kilometer deep soft rock high ground stress underground projects. 展开更多
关键词 No pillar mining Overhead mining NPR anchor cable physical model of similar materials FLAC3D Numerical simulation Motion of overburden
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Preparation of Ti-Mo getters by injection molding 被引量:2
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作者 Zhao, Zhenmei Wei, Xiuying +1 位作者 Xiong, Yuhua Mao, Changhui 《Rare Metals》 SCIE EI CAS CSCD 2009年第2期147-150,共4页
Ti-Mo getters have been fabricated via metal injection molding (MIM) using three kinds of Ti powders with different mean particle sizes of 46 μm,35 μm and 26 μm,respectively. The surface morphology,porosity,and hyd... Ti-Mo getters have been fabricated via metal injection molding (MIM) using three kinds of Ti powders with different mean particle sizes of 46 μm,35 μm and 26 μm,respectively. The surface morphology,porosity,and hydrogen sorption properties of Ti-Mo getters formed by MIM using paraffin wax as a principal binder constituent were examined. It has been proven that the powder injection molding is a viable forming technique for porous Ti-Mo getters. The particle size of Ti powders and the powder loading influence... 展开更多
关键词 materials physics and chemistry metal injection molding Ti-Mo getter sorption capacity loading POROSITY
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A perspective on regression and Bayesian approaches for system identification of pattern formation dynamics 被引量:2
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作者 Zhenlin Wang Bowei Wu +1 位作者 Krishna Garikipati Xun Huan 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2020年第3期188-194,共7页
We present two approaches to system identification, i.e. the identification of partial differentialequations (PDEs) from measurement data. The first is a regression-based variational systemidentification procedure tha... We present two approaches to system identification, i.e. the identification of partial differentialequations (PDEs) from measurement data. The first is a regression-based variational systemidentification procedure that is advantageous in not requiring repeated forward model solves andhas good scalability to large number of differential operators. However it has strict data typerequirements needing the ability to directly represent the operators through the available data.The second is a Bayesian inference framework highly valuable for providing uncertaintyquantification, and flexible for accommodating sparse and noisy data that may also be indirectquantities of interest. However, it also requires repeated forward solutions of the PDE modelswhich is expensive and hinders scalability. We provide illustrations of results on a model problemfor pattern formation dynamics, and discuss merits of the presented methods. 展开更多
关键词 Computational mechanics materials physics Pattern formation Bayesian inference Inverse problem
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Internal Friction in Rail Waist of BNb and BNbRE Steels 被引量:1
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作者 于宁 孙振岩 +2 位作者 戢景文 王云盛 任新建 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期474-479,共6页
The internal frictions of the specimens in the waist centre of the commercial BNb and BNbRE rails, which were left in air for two years, were measured. It is found that there is an obvious Snoek-Kê-Koester (SKK... The internal frictions of the specimens in the waist centre of the commercial BNb and BNbRE rails, which were left in air for two years, were measured. It is found that there is an obvious Snoek-Kê-Koester (SKK) peak in both steels, and still exists a measurable deformation-enhanced Shock peak(DESP) in the specimens of the BNbRE steel. The internal frictions in the deformed specimens of the both steel rails were also measured. Unlike the case of the tread specimens showing a decrease of SKK damping due to deformation, the SKK damping of the rail waist specimens increases after deformation; and the specimens containing rare earth(RE) show more noticeable damping increase than those without RE. The results of the internal friction measured during ascending and descending temperature under 700℃ show that there is a high temperature damping which can be completely disappeared during descending temperature for both steels. 展开更多
关键词 material physics mechanical spectrum internal friction rail steel rare earths
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Effects of Annealing Temperature on Microstructure and Sensing Properties to Alcohol for Nano-La_(0.68)Pb_(0.32)FeO_3
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作者 张玲 胡季帆 +3 位作者 秦宏伟 安康 宋鹏 侯万国 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第1期85-87,共3页
La_(0.68)Pb_(0.32)FeO_3 samples annealed at different temperature were prepared using citrate sol-gel method. With increasing of annealing temperature from 200 to 1000 ℃, the samples crystallize to have single-phase ... La_(0.68)Pb_(0.32)FeO_3 samples annealed at different temperature were prepared using citrate sol-gel method. With increasing of annealing temperature from 200 to 1000 ℃, the samples crystallize to have single-phase perovskite structure. However, the sensitivity increases at first due to the improvement of crystallization of the perovskite phase, and finally drops attributed to the larger grain size. The optimal sensitivities for La_(0.68)Pb_(0.32)FeO_3 samples annealed at 400, 600, 800, and 1000 ℃ are 12.14, 14.77, 51.07, and 34.55, respectively. 展开更多
关键词 materials physics and chemistry perovskite structure annealing temperature GAS-SENSING rare earths
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Synthesis and Electrical Properties of La_ 0.8Sr_(0.2)-x Ca_xCo_(0.9)Fe_ 0.1O_3-δ
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作者 谢刚 马文会 +2 位作者 陈书荣 崔衡 张雄飞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第1期94-97,共4页
Effects of small amount of Ca doping in La site in LaCoO 3-based oxide on th e synthesis and electrical conductivity were investigated by using X-ray diffra ction (XRD), differential scanning calorimetry and thermogr... Effects of small amount of Ca doping in La site in LaCoO 3-based oxide on th e synthesis and electrical conductivity were investigated by using X-ray diffra ction (XRD), differential scanning calorimetry and thermogravimetry (DSC/TG), or dinary four-probe dc measurement methods. La 0.8Sr 0.2-xCa x Co 0.9Fe 0.1O 3-δ (LSCCF, 0≤x≤0.1) prepared by solid r eact ion synthesis is all of a single phase and the calcined process may be divided i nt o three stages: (1) decomposition of reactants; (2) formation of LaCoO 3-based oxides; and (3) formation of LSCCF solid solution. The maximum of electrical co nductivity of the LSCCF composites is above 100 S·cm -1 and the co nduction me chanism is attributed to the adiabatic-hopping of p-type small polarons. 展开更多
关键词 material physical chemistry solid reaction synthesis compositely doped material solid oxide fuel cells rare earths
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Applications of low temperature calorimetry in material research
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作者 Xin Liu Jipeng Luo +2 位作者 Nan Yin Zhi-Cheng Tan Quan Shi 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第5期664-670,共7页
Low temperature calorimetry is an experimental method of heat capacity measurements, and heatcapacity is one of the most important and fundamental thermodynamic properties of substances. Theheat capacity can provide a... Low temperature calorimetry is an experimental method of heat capacity measurements, and heatcapacity is one of the most important and fundamental thermodynamic properties of substances. Theheat capacity can provide an average evaluation of the thermal property of a sample since it is a bull(property of substances. In the other hand, the condensed states of substances could be mainly controlledby the molecular motions, intermolecular interactions, and interplay among molecular structures. Thephysical property reflected in a material may be closely related to the energy changes in these threefactors, which can be directly observed in a heat capacity curve. Therefore, low temperature calorimetryhas been used not only to obtain heat capacity, entropy, enthalpy and Gibbs free energy, but also toinvestigate and understand lattice vibrations, metals, superconductivity, electronic and nuclearmagnetism, dilute magnetic systems and structural transitions. In this review, we have presented theconcept of low temperature calorimetry and its applications in the related field of material researches,such as nano-materials, magnetic materials, ferroelectric materials, phase change materials and othermaterials. 展开更多
关键词 Low Temperature Calorimetry Heat Capacity Thermodynamics physical Propertie materials
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Structure and Properties of Nanostructured Vacuum-Deposited Foils of Invar Fe–(35–38 wt%)Ni Alloys 被引量:3
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作者 V.M.Nadutov A.I.Ustinov +2 位作者 S.A.Demchenkov Ye.O.Svystunov V.S.Skorodzievski 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2015年第11期1079-1086,共8页
The process of electron beam vacuum deposition of the Fe-(35-38 wt%)Ni alloys at substrate temperatures Ts from 300 to700 ℃ were used to produce vacuum-deposited foils with the FCC structure, differing by the size ... The process of electron beam vacuum deposition of the Fe-(35-38 wt%)Ni alloys at substrate temperatures Ts from 300 to700 ℃ were used to produce vacuum-deposited foils with the FCC structure, differing by the size of characteristic microstructural elements (grains and subgrains). It was shown that refinement of foil microstructural elements to nanoscale is accompanied by their microhardness increase up to 4-5 GPa. The change of the thermal expansion coefficient (TEC) of the nanostructured (NS) foil of the Fe-35.1Ni alloy within the temperature range from -50 to 150 ℃ has some deviation from that observed for cast Invar alloy of the same composition. It has been found that the main factors affecting the peculiarities of thermal expansion of the NS foil can be related to the presence of small fraction of BCC- phase in them, high level of crystalline lattice microstrains and inhomogeneous magnetic order in FCC- phase. It was shown that as a result of additional thermal treatment of NS foils their invar properties become similar to that observed for cast Invar alloy but mechanical properties remain on the same level. 展开更多
关键词 Fe-Ni alloys Electron beam physical vapor deposition (EBPVD) Nanostructured materials Hardness Thermal expansion Mossbauer spectroscopy
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Studies of Water V. Five Phonons in Protonic Semiconductor Lattice Model of Pure Liquid Water
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作者 Binbin Jie Chihtang Sah 《Journal of Semiconductors》 EI CAS CSCD 2017年第7期1-17,共17页
We report physics based confirmation(~1% RMS deviation), by existing experimental data, of protonprohol(proton-hole) ion product(p H) and mobilities in pure liquid water(0-100℃, 1-atm pressure) anticipated fr... We report physics based confirmation(~1% RMS deviation), by existing experimental data, of protonprohol(proton-hole) ion product(p H) and mobilities in pure liquid water(0-100℃, 1-atm pressure) anticipated from our melted-ice Hexagonal-Close-Packed(H_2O)_4Lattice Model. Five phonons are identified.(1) A propagating protonic phonon(520.9 meV from lone-pair-blue-shifted stretching mode of isolated water molecule) absorbed to generate a proton-prohol pair or detrap a tightly-bound proton.(2) Two(173.4 and 196.6 meV) bending-breathing protonic-proholic or protonic phonons absorbed during de-trapping-limited proton or proton-prohol mobilities.(3)Two propagating oxygenic-wateric Debye-Dispersive phonons(30.3 and 27.5 meV) absorbed during scatteringlimited proton or proton-prohol mobilities. 展开更多
关键词 solid soft and liquid material physics pure water point-mass positive proton and negative prohol pH proton-ion product and mobilities phonon scattering and detrapping-trapping of propagating-localized protons and prohols
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Studies of Water Ⅵ. One-Band,Two-Band and Three-Band,Trappy,Protonic,Semiconductor Lattice Models for Pure Liquid Water
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作者 Binbin Jie Tianhui Jie Chihtang Sah 《Journal of Semiconductors》 EI CAS CSCD 2018年第11期1-7,共7页
This report adds three protonic semiconductor models to explain the "abnormally" high electrical conductivity of pure liquid water characterized by the three industrial consensus parameters, the ion product(... This report adds three protonic semiconductor models to explain the "abnormally" high electrical conductivity of pure liquid water characterized by the three industrial consensus parameters, the ion product(or pH)and the two ion mobilities. Existence of long-range order in fluid water under numerous daily conditions led us to extend the 1933 Bernal-Fowler hexagonally close packed crystalline Ice Lattice to model liquid water as Melted Ice. Protonic kinetic energy band and bound(trap) pictures provide semiconductor-physics based new models of these three parameters. They are extrapolatable engineered-models for developing novel biological, chemical, electrical, mechanical and medical applications of liquid water. 展开更多
关键词 solid and soft-fluid-liquid materials physics pure water point-mass positive proton and negativeprohol proton-ion product (pH) and mobilities propagating-and-localized phonon scattering anddetrapping-trapping of propagating-and-localized protons and prohols Protonic Fermionic Bosonsand Bosonic Fermions
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